Bahrain has banned three Muslim clerics from preaching in mosques, accusing them of violating the "ethics and principles of religious discourse", in what opposition activists said was part of a *****down on dissent. State news agency BNA said the Ministry of Justice and Islamic Affairs and Interior Ministry of the Sunni Muslim-ruled kingdom had forbidden Sheikh Kamel al-Hashemi, Adel al-Hamad and Mohammed al-Mansi to preach in and around the capital Manama. It said the three had ig**red warning from authorities to stick to rules set for preachers. Majority Shi'ites led mass protests in the island state in 2011.